Suspended Well Costs (Tables)

12 Months Ended

Dec. 31, 2013

Suspended Well Costs [Abstract]

Capitalized Exploratory Well Costs, Roll Forward [Table Text Block]

The following table reflects the net changes in capitalized exploratory well costs during 2013, 2012, and 2011. The table does not include amounts that were capitalized and either subsequently expensed or reclassified to producing well costs in the same year:

	For the Years Ended December 31,
	2013			2012			2011
	(in thousands)
Beginning balance on January 1,	$	9,100		$	18,600		$	35,862
Additions to capitalized exploratory well costs pending the determination of proved reserves	34,527			9,100			15,618
Reclassifications to wells, facilities, and equipment based on the determination of proved reserves	(9,100		)	(5,865		)	(32,880		)
Capitalized exploratory well costs charged to expense	—			(12,735		)	—
Ending balance at December 31,	$	34,527		$	9,100		$	18,600

Schedule of Aging of Capitalized Exploratory Well Costs [Table Text Block]

The following table provides an aging of capitalized exploratory well costs based on the date the drilling was completed and the number of projects for which exploratory well costs have been capitalized for more than one year since the completion of drilling:

	As of December 31,
	2013		2012		2011
	(in thousands)
Exploratory well costs capitalized for one year or less	$	34,527	$	9,100	$	15,618
Exploratory well costs capitalized for more than one year	—		—		2,982
Ending balance at December 31,	$	34,527	$	9,100	$	18,600
Number of projects with exploratory well costs that have been capitalized more than a year	—		—		2